One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

Satoru Tanaka

doi:10.1007/s12583-013-0366-6

Volume 24 Issue 5

Oct 2013

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Journal of Earth Science > 2013 > 24(5): 706-715.

Satoru Tanaka. One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere. Journal of Earth Science, 2013, 24(5): 706-715. doi: 10.1007/s12583-013-0366-6

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Satoru Tanaka. One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere. Journal of Earth Science, 2013, 24(5): 706-715. doi: 10.1007/s12583-013-0366-6

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One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

doi: 10.1007/s12583-013-0366-6

Satoru Tanaka^,

Institute for Research on Earth Evolution, Japan Agency for Marine-Earth Science and Technology, Yokosuka, 237-0061, Japan

Funds:

the Japan Society for the Promotion of Science (JSPS) KAKENHI 21340132

More Information

Corresponding author: Satoru Tanaka, stan@jamstec.go.jp
Received Date: 23 Nov 2012
Accepted Date: 04 Mar 2013
Publish Date: 01 Oct 2013

Abstract

Abstract

Attenuation of PKP(DF) in the Eastern Hemisphere is examined in terms of multiple scattering to simultaneously explain a puzzling relationship, a relatively fast velocity anomaly corresponding to strong attenuation. Reflectivity synthetics with one-dimensional random velocity fluctuations are compared with observations of PKP(DF)/PKP(Cdiff) amplitude ratios and differential travel times of PKP(Cdiff)-PKP(DF) for the equatorial paths. A Gaussian distribution of P-wave velocity fluctuations with the standard deviations of 5%, 6%, and 7% in the uppermost 200 km of the inner core is superimposed on the velocity structure that is slightly faster than the typical structure in the Eastern Hemisphere, which is likely to explain both the travel time and amplitude data as far as only the one-dimensional structure is considered. Further examinations of the statistic characteristic of scatterer distribution in two and three-dimensions are required to obtain a realistic conclusion.
- seismology,
- the inner core,
- attenuation,
- scattering

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References(35)

References

Braginsky, S. J., 1963. Structure of the F Layer and Reasons for Convection in the Earth's Core. Dokl. Akad. Nauk SSSR, 149: 8–10

Calvet, M., Margerin, L., 2008. Constraints on Grain Size and Stable Iron Phases in the Uppermost Inner Core from Multiple Scattering Modeling of Seismic Velocity and Attenuation. Earth Planet. Sci. Lett. , 267(1–2): 200–212

Cao, A., Romanowicz, B., 2004. Hemispherical Transition of Seismic Attenuation at the Top of the Earth's Inner Core. Earth Planet. Sci. Lett. , 228(3–4): 243–253 http://www.onacademic.com/detail/journal_1000035381303110_d429.html

Cormier, V. F., Li, X., Choy, G. L., 1998. Seismic Attenuation of the Inner Core: Viscoelastic or Stratigraphic. Geophys. Res. Lett. , 25(21): 4019–4022 doi: 10.1029/1998GL900074

Cormier, V. F., Li, X., 2002. Frequency-Dependent Seismic Attenuation in the Inner Core 2. A Scattering and Fabric Interpretation. J. Geophys. Res. , 107(B12): ESE 14-1–ESE 14-15, doi: 10.1029/2002JB001796

Cormier, V. F., 2007. Texture of the Uppermost Inner Core from Forward- and Back-Scattered Seismic Waves. Earth Planet. Sci. Lett. , 258(3–4): 442–453

Deguen, R., 2012. Structure and Dynamics of Earth's Inner Core. Earth Planet. Sci. Lett. , 333–334: 211–225 http://www.onacademic.com/detail/journal_1000035380621110_2909.html

Hollerbach, R., Jones, C., 1993. Influnece of the Earth's Inner Core on Geomagnetic Fluctuations and Reversals. Nature, 365: 541–543 doi: 10.1038/365541a0

Kennett, B. L. N., 1988. Systematic Approximations to the Seismic Wavefield. In: Doornbos, D. J., ed., Seismological Algorithms: Computational Methods and Computer Programs. Academic Press, London. 237–259

Knuth, D. E., 1997. Seminumerical Algorithms, 3rd ed. Addison-Wesely, Reading, Massachusetts. 762

Leyton, F., Koper, K. D., 2007. Using PKiKP Coda to Determine Inner Core Structure: 2. Determination of QC. J. Geophys. Res. , 112(B5): doi: 10.1029/2006jb004370

Li, X., Cormier, V. F., 2002. Frequency-Dependent Seismic Atteunuation in the Inner Core, 1. A Viscoelastic Interpretation. J. Geophys. Res. , 107(B12): ESE 13-1–ESE 13-20 doi: 10.1029/2002JB001795

Lister, J., Buffett, B., 1995. The Strength and Efficiency of Thermal and Compositional Convection in the Geodynamo. Phys. Earth Planet. Inter. , 91: 17–30 doi: 10.1016/0031-9201(95)03042-U

Liu, H. P., Anderson, D. L., Kanamori, H., 1976. Velocity Dispersion due to Anelasticity Implications for Seismology and Mantle Composition. Geophys. J. Int. , 47: 41–58 doi: 10.1111/j.1365-246X.1976.tb01261.x

Monnereau, M., Calvet, M., Margerin, L., et al., 2010. Lopsided Growth of Earth's Inner Core. Science, 328(5981): 1014–1017 doi: 10.1126/science.1186212

Montagner, J. P., Kennett, B. L. N., 1996. How to Reconcile Body-Wave and Normal-Mode Reference Earth Models. Geophys. J. Int. , 125(1): 229–248 doi: 10.1111/j.1365-246X.1996.tb06548.x

Morelli, A., Dziewonski, A. M., Woodhouse, J. H., 1986. Anisotropy of the Inner Core Inferred from PKIKP Travel-Times. Geophys. Res. Lett. , 13(13): 1545–1548 doi: 10.1029/GL013i013p01545

Müller, G., 1985. The Reflectivity Method—A Tutorial. J. Geophys. Res. , 58(1–3): 153–174 http://www.researchgate.net/publication/279591207_The_reflectivity_method_a_tutorial

Press, W. H., Teukolsky, S. A., Vetterling, W. T., et al., 1988. Numerical Recipes in C: The Art of Scientific Computing. Cambridge Unversity Press, Cambridge. 994 http://academic.oup.com/ej/article/104/424/725/5158778

Ryberg, T., Tittgemeyer, M., Wenzel, F., 2000. Finite Difference Modeling of P-Wave Scattering in the Upper Mantle. Geophys. J. Int. , 141(1): 787–800 doi: 10.1046/j.1365-246x.2000.00117.x

Sato, H., Fehler, M., 1997. Seismic Wave Propagaion and Scattering in the Heterogeneous Earth. Springer, Berlin. 308 http://www5.unitn.it/Biblioteca/it/Web/EngibankFile/2921434.pdf

Song, X. D., Richards, P. G., 1996. Seismological Evidence for Differential Rotation of the Earth's Inner Core. Nature, 382(6588): 221–224 doi: 10.1038/382221a0

Song, X. D., Helmberger, D. V., 1998. Seismic Evidence for an Inner Core Transition Zone. Science, 282(5390): 924–927 doi: 10.1126/science.282.5390.924

Souriau, A., Romanowicz, B., 1996. Anisotropy in Inner Core Attenuation: A New Type of Data to Constrain the Nature of the Solid Core. Geophys. Res. Lett. , 23: 1–4 doi: 10.1029/95GL03583

Souriau, A., 2007. Deep Earth Structure—The Earth's Cores. In: Romanowicz, B., Dziewonski, A. M., eds., Treatise on Geophysics, Vol. 1, Seismology and Structure of the Earth. Elsevier, Amsterdam. 655–693

Sumita, I., Bergman, M., 2009. Inner-Core Dynamics. In: Olson, P., ed., Treatise on Geophysics, Vol. 8, Core Dynamics. Elsevier, Amsterdam. 299–318

Tanaka, S., Hamaguchi, H., 1997. Degree One Heterogeneity and Hemispherical Variation of Anisotropy in the Inner Core from PKP(BC)-PKP(DF) Times. J. Geophys. Res. , 102(B2): 2925–2938 doi: 10.1029/96JB03187

Tanaka, S., 2012. Depth Extent of Hemispherical Inner Core from PKP(DF) and PKP(Cdiff) for Equatorial Paths. Phys. Earth Planet. Inter. , 210–211: 50–62 http://seismo.snu.ac.kr/class/summary/2013/TanakaS.PEPI.V210.P50.2012.Summary.pdf

Tittgemeyer, M., Wenzel, F., Fuchs, K., et al., 1996. Wave Propagation in a Multiple-Scattering Upper Mantle—Observations and Modeling. Geophys. J. Int. , 127(2): 492–502 doi: 10.1111/j.1365-246X.1996.tb04735.x

Tkalčić, H., 2010. Large Variations in Travel Times of Mantle-Sensitive Seismic Waves from the South Sandwich Islands: Is the Earth's Inner Core a Conglomerate of Anisotropic Domains?. Geophys. Res. Lett. , 37: L14312, doi:143 10.11029/12010GL043841

Watanabe, T., Natori, M., Oguni, T., 1989. Numerical Calculation Softwares with Fortran77 (in Japanese). Maruzen, Tokyo. 325 http://www.mendeley.com/catalog/numerical-recipes-fortran-77-1/

Wen, L., Niu, F., 2002. Seismic Velocity and Attenuation Structures in the Top of the Earth's Inner Core. J. Geophys. Res. , 107(B11): doi: 10.1029/2001JB000170

Woodhouse, J. H., Giardini, D., Li, X. D., 1986. Evidence for Inner Core Anisotropy from Free Oscillations. Geophys. Res. Lett. , 13(13): 1549–1552 doi: 10.1029/GL013i013p01549

Yu, W. C., Wen, L., Niu, F., 2005. Seismic Velocity Structure in the Earth's Outer Core. J. Geophys. Res. , 110(B2): doi: 10.1029/2003JB002928

Yu, W. C., Wen, L., 2006. Seismic Velocity and Attenuation Structures in the Top 400 km of the Earth's Inner Core along Equatorial Paths. J. Geophys. Res. , 111(B7): B07308, doi:073 10.01029/02005JB00399

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One-Dimensional Modeling of Multiple Scattering in the Upper Inner Core: Depth Extent of a Scattering Region in the Eastern Hemisphere

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